1. Field of the Invention
This invention relates to a method of beaming elastomeric fibers onto a beam at high stretch and, more specifically, to a method where the beam stretch is about 200-400% absolute which is about 35%-75% of the elongation-to-break of the fibers.
2. Discussion of Related Art
Certain types of fabrics, for example warp knits and wovens, require that at least one of the fibers used to make the fabric be wound ("warped") onto beams from which they will be later unwound during the knitting or weaving process. The warp in such knits and wovens can be an elastomeric fiber.
During beaming of elastomeric fibers from a creel of fiber packages, it is customary during knitting and weaving to stretch the fibers slightly in order to remove them from the packages and to maintain sufficient fiber tension for easier handling. Such traditional stretching is generally in the range of about 10%-210%. The stretch on the beam ("beam stretch") which is customarily applied during commercial operations is generally in the range of about 25-105%. U.S. Pat. No. 4,525,905 discloses 80% pre-stretch (a constant extension between payout rollers and tension rollers) and 40% beam-stretch. Japanese Patent Application JP09-194892, filed Jul. 4, 1997, discloses pre-stretch of 250-500% and 50-130% beam-stretch.
However, fabrics, for example warp-stretch wovens and warp knits, made from beams of elastomeric fibers prepared according to the prior art have relatively high "power"; that is, they do not stretch easily. To obtain the low power desired for more comfortable garments, the knitting tension of the elastomeric fiber must be lowered, but lower stretch and higher spandex content also result. Higher knitting tension can be used to increase stretch and reduce spandex content but this would put undesirable strain on the knitting needles, thus shortening the needles' useful life, and the knitting machine must be operated more slowly.
A method of preparing fabrics with "easy" stretch (low power) and high stretch without deleteriously affecting equipment is still needed.